On Fri, 2007-10-26 at 13:23 +0200, Ingo Molnar wrote:> * Zhang, Yanmin <yanmin_zhang@linux.intel.com> wrote:> > > I tested 2.6.24-rc1 on my x86_64 machine which has 2 quad-core processors.> > > > Comparing with 2.6.23, aim7 has about -30% regression. I did a bisect > > and found patch > > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=b5869ce7f68b233ceb81465a7644be0d9a5f3dbb> > caused the issue.> > weird, that's a commit diff - i.e. it changes no code.I got the tag from #git log. As for above link, I just added prior http address,so readers could check the patch by clicking.

> > > kbuild/SPECjbb2000/SPECjbb2005 also has big regressions. On my another > > tigerton machine (4 quad-core processors), SPECjbb2005 has more than > > -40% regression. I didn't do a bisect on such benchmark testing, but I > > suspect the root cause is like aim7's.> > these two commits might be relevant:> > 7a6c6bcee029a978f866511d6e41dbc7301fde4cI did a quick testing. This patch has no impact.

> 95dbb421d12fdd9796ed153853daf3679809274fAbove big patch doesn't include this one, which means if I do'git checkout b5869ce7f68b233ceb81465a7644be0d9a5f3dbb', the kernel doesn't include95dbb421d12fdd9796ed153853daf3679809274f.

> > but a bisection result would be the best info.I will do a bisect between 2.6.23 and tag 9c63d9c021f375a2708ad79043d6f4dd1291a085.